1. Field of Invention
The present invention relates to pressure sensing equipment for use with cylinders and tanks which hold compressed gas for dispersion under a lower and regulated pressure. More particularly, it relates to a device configured for removable mounting in combination with a portable high pressure gas cylinder and a regulator used to regulate the high pressure gas supplied by the cylinder. Such portable gas tanks or cylinders are commonly used to provide a portable oxygen supply to a user requiring such. The device features one or a combination of alarms, from a group of alarms including audio, visual, electronic, and remotely transmitted alarms. The alarm signal from the device alerts the user, or a third party monitoring the user, when remaining high pressure gas inside the gas cylinder drops below a predetermined level.
2. Prior Art
Cylinders and tanks containing pressurized gasses are used throughout the industrialized world in industry and medicine, the military, aviation, and other instances where a constant supply of regulated gas is required. Such pressurized tanks conventionally are made from high tensile strength material such as steel, aluminum, or resin impregnated fiberglass fibers as they must contain gases inside under extremely high pressures. The gas contained in such cylinders can range from 20 cubic feet to 300 cubic feet or more at pressures as high as 2500 pounds per square inch.
It is desirable to monitor internal tank pressure of the supply cylinder to continually ascertain the remaining usable gas supply in the canister. This is especially true in the case of portable oxygen supply tanks used in medical, aviation, emergency, and other situations as the life of the user may depend upon a constant supply of oxygen for breathing.
Currently, in conventionally used devices, internal tank pressure is monitored by a mechanical gauge, which is attached to a conventional regulator used to reduce incoming high pressure from the tank to useable pressures for the patient to breathe or for industrial uses such as welding. The embodiments of the device disclosed herein are directed at an improved supply tank gas pressure monitoring system using one or a combination of audible alarms, visual alarms, or electronically transmitted, warnings about low pressure and diminishing reserves in the supply tank.
The improved pressure alert system features flashing lights to visually warn of lower than desired pressure. Additionally, an audible buzzer alarm may be employed to alert the user with poor sight or poor attention, to the lowering of pressure below the predetermined level. Further, an optional radio, infrared, or a similar transmitter, can update a central station, computer, or other device configured to receive the digital or analog information regarding remaining pressure which is transmitted by the on board microprocessor communicating through the transmitter.
Conventionally used air tank pressure gauges currently feature a regulator for lowering and regulating internal tank pressure to useable levels combined with a mechanical gauge that displays remaining internal tank pressure. Such regulators need to be quickly connected and disconnected especially when a user is breathing the tank gas, as in the case of a portable oxygen tank used to aid breathing. These supply tanks conventionally feature a compression fitting that seals between the tank outlet aperture and a regulator inlet aperture once compressed in an operative mounting by a compression clamp that is secured around the neck of the tank. A sealed conduit from the tank through the regulator to the user's mask is thereby achieved. The compression clamp used to removably mount the regulator to the tank operates using a handle or other manner of compression to compress the regulator toward the outlet aperture from the tank. A seal is formed between the inlet aperture of the regulator and the outlet aperture of the tank forming a communicating conduit between the two. This mode of attachment provides for easy attachment and detachment of the regulator from the supply tank when a tank change is needed to renew the available gas supply to the user.
This mode of operation, while quick for the user, also has its drawbacks. This is especially true when it comes to communicating remaining tank pressure to the user and to others who would have a prime interest in knowing the remaining tank pressure and thus the remaining volume of compressed gas available for use.
Pressure gauges now conventionally attached to a port in the regulator communicating with the high incoming pressure from the tank, can be hard to read by users with poor eyesight. Such gauges can also be hard to understand for those who are not technically oriented, or do not know what a safe operating pressure actually is for the supply tank or cylinder.
Users in need of oxygen to breathe properly, frequently wear a mask to communicate oxygen from the supply tank to their nose and/or mouth for breathing. Such users may be of ill health from a pulmonary or cardiovascular disease and severely dependent upon a reliable and continued oxygen supply. Other users dependent upon a constant and reliable supply of oxygen include aircraft pilots, fireman and emergency personnel, and military and industrial users. It is therefor imperative that such users comprehend when the remaining tank pressure of the supply tank and volume of gas therein available for breathing, drops below a point deemed prudent. To allow the pressure to dissipate entirely in a medical or emergency situation would risk the user's life support provided by the supply of oxygen. Failure to maintain adequate supplies of oxygen and other gases in industrial and military situations can be costly in time and money from resulting downtime.
The most dependent users of such oxygen supplies are generally health impaired, aged, and/or not technically oriented. The tendencies of such individuals to misinterpret the conventional gauge, or fall asleep while using the oxygen mask, are therefor greatly increased. Other users in emergencies or industrial situations may not be as attentive to the remaining oxygen supply in the tank due to distractions on the job during use of the supply tank. Consequently, a simple and easy to it understand system, to warn such users of impending depletion of the gas supply, would be of great benefit. Additional benefit would be derived in situations where third parties who monitor the remaining tank supply of the users. This benefit is provided by the audible, and visual alarms on the device along with the remote monitoring capabilities of the device decreasing the level of attentiveness required to monitor the continuing diminishing air supply in the supply tank. With such a visual, audible, or transmitted alarm, to warn monitoring parties of the dangerous condition that has occurred once tank pressure has dropped below a prudent level, the person monitoring the supply available to the user may be confident that a short lapse of attention in constantly monitoring a mechanical gauge, will no longer cause drastic consequences.
Industrial users of compressed gas would also benefit from such a remote warning device that is easily attachable and detachable to a tank and regulator using conventional mounting brackets and fittings. Welders in need of constant supplies of oxygen, acetylene, and in some cases nitrogen gas supplies, would be better able to concentrate on their work with the knowledge that they will be alerted audibly and visually to tank pressure drops below what is considered operational.
Further, if fitted with a radio, infrared, or other style transmitter, that transmits information concerning remaining tank pressure to a receiving station, supply cylinders that have reached a predetermined level to low to be considered acceptable, would immediately activate a remote alarm or signal. This would allow a central monitoring station in a town or in a hospital or other venue with large numbers of tanks in use, to be immediately informed when a supply tank is reaching critical level. One person could monitor many such supply tanks remotely, and can dispatch someone to replace or recharge tanks that have reached a dangerous or low level.
The device herein disclosed can also be configured whereby the on board transmitter is activated by a remote signal from a central monitoring station, to transmit the remaining tank pressure in the supply tank. In airports, hospitals, and industrial and military uses, a single monitoring station could thus monitor the remaining gas levels in hundreds of supply tanks, thus allowing for better inventory maintenance and replacement of depleted supply tanks.
Prior art has attempted to address some of the aforementioned problems and solutions but without great success.
U.S. Pat. No. 4,176,617 (Pilipski) teaches a low pressure alarm to monitor pressure in containers. However, Pilipski is a complicated array of conduits, offers no manner for easy mounting of the device in a compressed gas circuit for easy removal and remounting, nor does it provide any visual alarm to the hearing impaired or sleeping users.
U.S. Pat. No. 5,040,477 (Shiffmacher) provides for an audible alarm to warn of dwindling air supplies in a portable compressed air tank. However Shiffmacher is designed for threaded engagement with a tank and contains numerous springs and valves that can malfunction. It is thus not easily incorporated for mounting and dismounting with the millions of conventional compression clamp style devices currently in use. Further, it offers no visual alarm nor remote signaling options.
U.S. Pat. No. 5,057,822 (Hoffman) addresses the issue of a warning of low pressure in a pressurized gas system servicing a plurality of patients in a hospital or other setting. Hoffman however is designed for permanent mounting in the system and is not easily mounted and dismounted on the millions of portable units using a compression clamp style fitting to access the internal air supply through a regulator.
As such, there exists a need for an easily and inexpensively manufactured multi functional warning system which is easily mounted and dismounted from the millions of conventionally used pressurized tanks which employ a compression clamp mount of the regulator to the tank. Such a device should offer a plurality of alarm modes such that those with poor eyesight could be warned of a problem with a bright blinking light. Such a device should also offer an audible alarm to awaken sleeping or inattentive users to the impending pressure drop below functional norms. Such a device should also be capable of optionally transmitting actual pressure when queried from a remote location or automatically if tank pressure drops below norms.